Mobility has become a key concern in cities throughout both the developed and developing world, as it profoundly affects the livelihoods and lifestyles of many millions of urban dwellers. The 20th century was a period of rapid motorization, bringing with it enormous social and economic benefits. Motor vehicles have enabled people to be flexible with regards to where they live and work, providing ready access to a variety of services and leisure options. They have also been instrumental in facilitating the rapid and timely distribution of manufactured goods. But the widespread use of vehicles also brings real environmental and economic costs. These costs have risen dramatically in the past few decades and vehicles now represent a major source of air pollution and global greenhouse gas emissions. The increase in the use of vehicles also represents a genuine threat to economic security for many nations, due to the need to import oil to fuel them.

City authorities have sought to address these problems by encouraging people to use more sustainable methods of travel such as public transport, cycling and walking. Measures to cut demand and rein in car use are an important component in seeking to achieve a modal shift away from oil-dependent transportation. Urban transport measures can also assist in achieving wider objectives. Pricing structures, for example, can contribute towards a city's equity objectives. The promotion of cycling and walking can bring about considerable benefits in terms of health and well-being, which could reduce costs associated with healthcare provision. Social inclusion should be an important consideration in every city's transport policy, to ensure that all citizens have access to transport options, including those with disabilities, the elderly and other vulnerable groups.

Investment in urban transport and communications infrastructure is critical for balanced regional development and for the enhancement of economic potential in urbanized areas. In the developing world, targeted investment in transport and communications infrastructure continues to drive significant growth and economic development.

This section's knowledge cards cover these and other aspects of global urban mobility. They provide examples of best practice and have been designed to inspire and inform. Please note that given our chosen area of focus is urban mobility, we have not included best practice in inter-urban and longer distance transportation - airports, ports, intercity rail and other modes of long distance travel are not examined.